The present invention relates to filtering means for recirculating air systems and, in particular, to a cartridge filter/cover which is mountable within supply and return registers.
Commercial and residential heating and cooling systems have long utilized a filter element in close proximity to a blower or fan means which induces airflow through the ducted system. Such filters are commonly mounted within prepared slideways formed in the ductwork or plenums adjacent the air source. The filter media may also comprise a sheet stock material which is mounted within a bordering retainer. Alternatively, the sheet filter meedia may be supported from a wire frame assembly or other framework within a plenum portion of the system.
Known filter mountings however do not filter the plurality of inlets and outlets of the duct system, nor provide means for the filter to separately attach to the air handling system, nor permit selective closure of the plurality of inlets and outlets.
During the construction process of most residential and commercial buildings, air handling ductwork is installed before the wall and flooring materials are added. Consequently, once the ductwork is roughed-in with all inlet and outlet ports commonly left exposed and may collect debris. On occasion, builders may insert pieces of fiberglass batting to fill one or more outlets and prevent the collection of construction debris. Such batting is not intended to permit operation of the system, but merely plug the passage to debris.
Over the life and operation of the system, any debris within the ductwork can be repeatedly re-circulated. During the initial period of system operation, dust re-circulation can be especially troublesome. Most troublesome is dust which accumulates from the preparation of sheetrock walls. This dust is extremely fine and can be repeatedly circulated over many weeks, once the ventilating system is initiated.
Depending upon the climate, it may also be necessary on occasion to operate the heating or cooling system during the construction process. Plugged ducts must then be exposed and debris may collect in the system. Although debris might later be vacuumed with the final preparation of the home, the operation of the system tends to distribute the dust throughout the system, with subsequent redistribution through the building.
Applicant accordingly has sought to develop a filter cartridge which readily accommodates use during building construction either as a plug or a filter. The assembly has also been designed to permit use by the homeowner within all or selected rooms of the heating system to further filter either the supply or return air conducted through the selected rooms.